Installed radio now blower fan does not run?

LEO8A12

MEMBER
1999 HONDA CIVIC
4 CYL
2WD
AUTOMATIC
120,000 MILES

I have installed a radio into a 99 honda civic equipped with cassette player also, after the installation the a/c blower fan did not work properly The connection is not lose on the a/c controls. The fuse is also not blown. Maybe a resistor?Please help Thank you very much

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

Inoperative blower fan can be due to a bad blower relay, wiring issue or a bad resistor or the motor itself.

The blower relay is located in the under-hood fuse box (see diagram below).
Check for any corrosion or burnt pin(s).
This relay can also be tested:

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

If the relay is good and there is power to the blower motor, then the issue is likely a bad blower motor.

https://www.2carpros.com/articles/blower-fan-motor-works-on-high-speed-only

You also want to make sure that none of the wire got loose/disconnected or pinched during the radio install.

I have attached diagrams for your reference.

Please let me know if you have any questions.
Thank you.

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